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1.
Antioxidants (Basel) ; 13(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38397790

RESUMO

The increasing world population means an increased demand for sustainable processes and products related to foods, particularly those with added health benefits. Plants can be an alternative source of nutritional and biofunctional ingredients. Cytisus plants are an underexploited bioresource, currently prevalent in the Mediterranean Basin and western Asia. This manuscript addresses the processing potential of Cytisus plants for the development of added-value products, including food formulations, food packaging, cosmetics, and therapeutic applications. Most research has reported that Cytisus spp. are a promising source of inexpensive bioactive polyphenol compounds. Cytisus flowers should be considered and exploited as raw materials for the development of new food ingredients (antioxidants, preservatives, additives, etc.), nutraceuticals, or even direct therapeutic agents (anticancer, antibacterial, etc.). In order to evaluate the socioeconomic effect of these underutilized plants, more research is needed to assess their valorization for therapeutic and dietary possibilities, as well as the economic impact.

2.
Front Bioeng Biotechnol ; 11: 1136077, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37576995

RESUMO

Skin indicates a person's state of health and is so important that it influences a person's emotional and psychological behavior. In this context, the effective treatment of wounds is a major concern, since several conventional wound healing materials have not been able to provide adequate healing, often leading to scar formation. Hence, the development of innovative biomaterials for wound healing is essential. Natural and synthetic polymers are used extensively for wound dressings and scaffold production. Both natural and synthetic polymers have beneficial properties and limitations, so they are often used in combination to overcome overcome their individual limitations. The use of different polymers in the production of biomaterials has proven to be a promising alternative for the treatment of wounds, as their capacity to accelerate the healing process has been demonstrated in many studies. Thus, this work focuses on describing several currently commercially available solutions used for the management of skin wounds, such as polymeric biomaterials for skin substitutes. New directions, strategies, and innovative technologies for the design of polymeric biomaterials are also addressed, providing solutions for deep burns, personalized care and faster healing.

3.
Nanomaterials (Basel) ; 12(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35808060

RESUMO

The impact of nanotechnology on the exponential growth of several research areas, particularly nanomedicine, is undeniable. The ability to deliver active molecules to the desired site could significantly improve the efficiency of medical treatments. One of the nanocarriers developed which has drawn researchers' attention are cubosomes, which are nanosized dispersions of lipid bicontinuous cubic phases in water, consisting of a lipidic interior and aqueous domains folded in a cubic lattice. They stand out due to their ability to incorporate hydrophobic, hydrophilic, and amphiphilic compounds, their tortuous internal configuration that provides a sustained release, and the capacity to protect and safely deliver molecules. Several approaches can be taken to prepare this structure, as well as different lipids like monoolein or phytantriol. This review paper describes the different methods to prepare nanocarriers. As it is known, the physicochemical properties of nanocarriers are very important, as they influence their pharmacokinetics and their ability to incorporate and deliver active molecules. Therefore, an extensive characterization is essential to obtain the desired effect. As a result, we have extensively described the most common techniques to characterize cubosomes, particularly nanocarriers. The exceptional properties of the cubosomes make them suitable to be used in several applications in the biomedical field, from cancer therapeutics to imaging, which will be described. Taking in consideration the outstanding properties of cubosomes, their application in several research fields is envisaged.

4.
Molecules ; 27(5)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35268769

RESUMO

"Flawless skin is the most universally desired human feature" is an iconic statement by Desmond Morris. Skin indicates one´s health and is so important that it affects a person's emotional and psychological behavior, these facts having propelled the development of the cosmetics industry. It is estimated that in 2023, this industry will achieve more than 800 billion dollars. This boost is due to the development of new cosmetic formulations based on nanotechnology. Nanocarriers have been able to solve problems related to active ingredients regarding their solubility, poor stability, and release. Even though nanocarriers have evident benefits, they also present some problems related to the high cost, low shelf life, and toxicity. Regulation and legislation are two controversial topics regarding the use of nanotechnology in the field of cosmetics. In this area, the U.S. FDA has taken the lead and recommended several biosafety studies and post-market safety evaluations. The lack of a global definition that identifies nanomaterials as a cosmetic ingredient is a hindrance to the development of global legislation. In the EU, the legislation regarding the biosafety of nanomaterials in cosmetics is stricter. "The cost is not the only important issue, safety and the application of alternative testing methods for toxicity are of crucial importance as well".


Assuntos
Cosméticos , Nanoestruturas , Composição de Medicamentos , Humanos , Nanotecnologia , Pele
5.
FEMS Microbiol Ecol ; 98(4)2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35298615

RESUMO

Within the oral cavity, the ability of Candida species to adhere and form biofilms is well-recognized, especially when Candida albicans is considered. Lately, a knowledge gap has been identified regarding dual-species communication of Candida isolates, as a way to increase virulence, with evidences being collected to support the existence of interactions between C. albicans and Candida parapsilosis. The present work evaluated the synergistic effect of the two Candida species, and explored chemical interactions between cells, evaluating secreted extracellular alcohols and their relation with yeasts' growth and matrix composition. A total of four clinical strains of C. albicans and C. parapsilosis species, isolated from single infections of different patients or from co-infections of a same patient, were tested. It was found that dual-species biofilms negatively impacted the growth of C. parapsilosis and their biofilm matrix, in comparison with mono-species biofilms, and had minor effects on the biofilm biomass. Alcohol secretion revealed to be species- and strain-dependent. However, some dual-species cultures produced much higher amounts of some alcohols (E-nerolidol and E, E-Farnesol) than the respective single cultures, which proves the existence of a synergy between species. These results show evidence that interactions between Candida species affect the biofilm matrix, which is a key element of oral biofilms.


Assuntos
Candida albicans , Candida parapsilosis , Álcoois/metabolismo , Álcoois/farmacologia , Biofilmes , Candida , Candida parapsilosis/metabolismo , Humanos , Metaboloma
6.
Antioxidants (Basel) ; 10(9)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34573107

RESUMO

Natural bioactive compounds from food waste have fomented interest in food and pharmaceutical industries for the past decade. In this work, it purposed the recovery of bioactive avocado peel extract using an environmentally friendly technique: the ultrasound assisted extraction. The response surface methodology was applied in order to optimize the conditions of the extraction, ethanol-water mixtures and time. The optimized extracts (ethanol 38.46%, 44.06 min, and 50 °C) were chemically characterized by HPLC-ESI-MS and FTIR. Its antioxidant ability, as well as, its effect on cell metabolic activity of normal (L929) and cancer (Caco-2, A549 and HeLa) cell lines were assessed. Aqueous ethanol extracts presented a high content in bioactive compounds with high antioxidant potential. The most representative class of the phenolic compounds found in the avocado peel extract were phenolic acids, such as hydroxybenzoic and hydroxycinnamic acids. Another important chemical group detected were the flavonoids, such as flavanols, flavanonols, flavones, flavanones and chalcone, phenylethanoids and lignans. In terms of its influence on the metabolic activity of normal and cancer cell lines, the extract does not significantly affect normal cells. On the other hand, it can negatively affect cancer cells, particularly HeLa cells. These results clearly demonstrated that ultrasound is a sustainable extraction technique, resulting in extracts with low toxicity in normal cells and with potential application in food, pharmaceutical or nutraceutical sectors.

7.
Biomolecules ; 11(8)2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34439888

RESUMO

The main goal of this study was to chemically characterize an aqueous S. nigra flower extract and validate it as a bioactive agent. The elderflower aqueous extraction was performed at different temperatures (50, 70 and 90 °C). The extract obtained at 90 °C exhibited the highest phenolic content and antiradical activity. Therefore, this extract was analyzed by GC-MS and HPLC-MS, which allowed the identification of 46 compounds, being quercetin and chlorogenic acid derivatives representative of 86% of the total of phenolic compounds identified in hydrophilic fraction of the aqueous extract. Naringenin (27.2%) was the major compound present in the lipophilic fraction. The antiproliferative effects of the S. nigra extract were evaluated using the colon cancer cell lines RKO, HCT-116, Caco-2 and the extract's antigenotoxic potential was evaluated by the Comet assay in RKO cells. The RKO cells were the most susceptible to S. nigra flower extract (IC50 = 1250 µg mL-1). Moreover, the extract showed antimicrobial activity against Gram-positive bacteria, particularly Staphylococcus aureus and S. epidermidis. These results show that S. nigra-based extracts can be an important dietary source of bioactive phenolic compounds that contribute to health-span improving life quality, demonstrating their potential as nutraceutical, functional foods and/or cosmetic components for therapeutic purposes.


Assuntos
Proliferação de Células/efeitos dos fármacos , Flores/química , Bactérias Gram-Positivas/efeitos dos fármacos , Fenóis , Extratos Vegetais/farmacologia , Sambucus nigra/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Humanos , Fenóis/química , Fenóis/farmacologia
8.
J Biophotonics ; 11(9): e201700323, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29537137

RESUMO

Epidermal growth factor receptor (EGFR) plays a key role in regulating cell survival, proliferation and migration, and its overexpression and activation has been correlated with cancer progression. Cancer therapies targeting EGFR have been applied in the clinic with some success. We show, by confocal microscopy analysis, that illumination of adenocarcinomic human alveolar basal epithelial cells (Human A549-EGFR biosensor cell line) with 280 nm at irradiance levels up to 20 times weaker than the Ultraviolet B (UVB) solar output for short periods of time (15-45 minutes) prevents epidermal growth factor-mediated activation of EGFR located on the cell membrane, preventing or reducing cellular disaggregation, formation of filopodia and cell migration. This effect of Ultraviolet (UV) light illumination was confirmed further in a functional scratch assay, and shown to be more effective than that of a specific EGFR-signaling inhibitor. This new photonic approach may be applicable to the treatment of various types of cancer, alone or in combination with other therapies.


Assuntos
Movimento Celular/efeitos da radiação , Receptores ErbB/metabolismo , Fótons/uso terapêutico , Células A549 , Humanos , Fatores de Tempo , Raios Ultravioleta
9.
Appl Microbiol Biotechnol ; 99(10): 4225-35, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25761624

RESUMO

Poly(hydroxybenzene)-trimethoprim conjugates were prepared using methylparaben as substrate of the oxidative enzyme tyrosinase. MALDI-TOF MS analysis showed that the enzymatic oxidation of methylparaben alone leads to the poly(hydroxybenzene) formation. In the presence of trimethoprim, the methylparaben tyrosinase oxidation leads poly(hydroxybenzene)-trimethoprim conjugates. All of these compounds were incorporated into lubricant hydroxyethyl cellulose/glycerol mixtures. Poly(hydroxybenzene)-trimethoprim conjugates were the most effective phenolic structures against the bacterial growth reducing by 96 and 97% of Escherichia coli and Staphylococcus epidermidis suspensions, respectively (after 24 h). A novel enzymatic strategy to produce antimicrobial poly(hydroxybenzene)-antibiotic conjugates is proposed here for a wide range of applications on the biomedical field.


Assuntos
Antibacterianos/farmacologia , Lubrificantes/farmacologia , Monofenol Mono-Oxigenase/química , Fenol/farmacologia , Trimetoprima/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Lubrificantes/síntese química , Lubrificantes/química , Espectrometria de Massas , Fenol/química , Staphylococcus epidermidis/efeitos dos fármacos , Trimetoprima/química
10.
Neurobiol Dis ; 40(1): 163-76, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20510362

RESUMO

Machado-Joseph disease (MJD) is a late-onset neurodegenerative disorder caused by a polyglutamine (polyQ) expansion in the ataxin-3 protein. We generated two transgenic mouse lineages expressing the expanded human ataxin-3 under the control of the CMV promoter: CMVMJD83 and CMVMJD94, carrying Q83 and Q94 stretches, respectively. Behavioral analysis revealed that the CMVMJD94 transgenic mice developed motor uncoordination, intergenerational instability of the CAG repeat and a tissue-specific increase in the somatic mosaicism of the repeat with aging. Histopathological analysis of MJD mice at early and late stages of the disease revealed neuronal atrophy and astrogliosis in several brain regions; however, we found no signs of microglial activation or neuroinflammatory response prior to the appearance of an overt phenotype. In our model, the appearance of MJD-like symptoms was also not associated with the presence of ataxin-3 cleavage products or intranuclear aggregates. We propose the transgenic CMVMJD94 mice as a useful model to study the early stages in the pathogenesis of MJD and to explore the molecular mechanisms involved in CAG repeat instability.


Assuntos
Corpos de Inclusão Intranuclear/metabolismo , Corpos de Inclusão Intranuclear/patologia , Doença de Machado-Joseph/patologia , Doença de Machado-Joseph/fisiopatologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Animais , Ataxina-3 , Modelos Animais de Doenças , Feminino , Humanos , Corpos de Inclusão Intranuclear/genética , Doença de Machado-Joseph/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Instabilidade de Microssatélites , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Neurônios/patologia , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Expansão das Repetições de Trinucleotídeos/genética
11.
J Nanosci Nanotechnol ; 9(6): 3714-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19504908

RESUMO

The use of bone grafts is required to restore skeletal integrity and enhance bone healing of large defects in several areas of regenerative medicine, such as: orthopedic and maxillofacial procedures. Some of these bone grafts can be resorbed in a time controlled way, in order to allow the correct process of natural re-construction of the involved bone tissue to occur. The Bonelike graft is a bone substitute that mimics the inorganic composition of bone; this biomaterial was developed and characterized over the last decade. In a granular form, Bonelike has proved its highly bioactive behavior in medical applications, such as; maxillofacial and orthopedics surgery. The clinical applications in maxillary bone defects indicated a good bone bonding between new formed bone and the Bonelike granules. The purpose of this study was to develop a new injectable system for the application of Bonelike using a resorbable vehicle which may be used in minimal invasive surgery. A new hydrogel derived from chitosan and y-glycidoxypropyltrimethoxysilane (GPTMS) was synthesized and characterized. The mixture derived from chitosan and GPTMS existed in sol state at room temperature and formed a hydrogel at 37 degrees C. The degradability of the hydrogel could be controlled by the concentration of chitosan and GPTMS, and the presence the presence of Bonelike did not affect its degradability. The pH changes caused by the degradation of this hydrogel were small, so it is not expected to cause any deleterious effect in vivo conditions.


Assuntos
Materiais Biocompatíveis , Osso e Ossos , Quitosana/química , Hidrogéis/síntese química , Próteses e Implantes , Silicatos/química , Hidrogéis/química , Microscopia Eletrônica de Varredura , Análise Espectral
12.
J Biomed Mater Res A ; 69(4): 670-9, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15162409

RESUMO

Recent histological studies have demonstrated that the substitution of silicate ions into hydroxyapatite (HA) significantly increases the rate of bone apposition to HA implants. The enhanced bioactivity of silicon-substituted HA (Si-HA) over pure HA has been attributed to the effect of silicate ions in accelerating dissolution. In the present study, high-resolution transmission electron microscopy (HR-TEM) was employed to compare dissolution of HA and Si-HA in an acellular simulated body fluid (SBF) to dissolution in an in vivo model. HR-TEM observations confirmed a difference in morphology of apatite precipitates in vivo and in SBF: apatite deposits were platelike in vivo and nodular in SBF. Compositional mapping suggested that preferential dissolution of silicon from the implant promotes the nucleation of carbonate apatite around the implant. The in vivo findings illustrated an absence of dissolution at the bone-HA or Si-HA interface, whereas dissolution was extensive from within the implant. The amount of dissolution in acellular SBF was similar to dissolution from within the implant, although the site at which the dissolution nucleates was different: dissolution predominates at the crystallite surfaces in SBF, whereas grain boundary dissolution predominates in vivo. These findings suggest that proteins in the in vivo milieu modify the processes of dissolution from the implant.


Assuntos
Materiais Biocompatíveis , Durapatita/química , Silício , Durapatita/síntese química , Microscopia Eletrônica , Microscopia Eletrônica de Varredura
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